#include <iostream>
#include <mutex>
#include <thread>

int main() {
    
    std::thread t1([=]() {
        std::cout << "Hello, Concurrent World 01 !\n";
        });

    std::thread t2([=]() {
        std::cout << "Hello, Concurrent World 02 !\n";
        });

    t1.join();
    t2.join();

    std::cout << "over!\n";
    return 0;
}
